title: International collaborative study on the occurrence of plasmid-mediated quinolone resistance in Salmonella enterica and Escherichia coli isolated from animals, humans, food and the environment in 13 European countries.
abstract: OBJECTIVE
  This study was initiated to collect retrospective information on the occurrence of plasmid-mediated quinolone resistance (PMQR) in Salmonella enterica and Escherichia coli isolates in Europe and to identify the responsible genes.
  
  
  METHODS
  Databases of national reference laboratories containing MIC values for Salmonella and E. coli isolated between 1994 and 2009 in animals, humans, food and the environment from 13 European countries were screened for isolates exhibiting a defined quinolone resistance phenotype, i.e. reduced susceptibility to fluoroquinolones and nalidixic acid. PCR and sequence analysis were performed to identify the responsible PMQR genes.
  
  
  RESULTS
  Screening of databases of 13 European countries resulted in a selection of 1215 Salmonella and 333 E. coli isolates. PMQR genes were identified in 59% of the Salmonella isolates and 15% of the E. coli isolates selected. In Salmonella, qnrS1 (n = 125) and variants of qnrB (n = 138) were frequently identified, whereas qnrA1 (n = 3) and aac(6')-1b-cr (n = 3) were rarely found. qnrD was detected in 22 Salmonella isolates obtained from humans and animals. In E. coli, qnrS1 was identified in 19 isolates and qnrB19 was found in one isolate. No qnrC or qepA genes were detected in either Salmonella or E. coli.
  
  
  CONCLUSIONS
  This study shows the occurrence and dissemination of PMQR genes in Salmonella and E. coli in Europe with a defined quinolone resistance phenotype. We also report the first detection of qnrD in Salmonella collected in Europe.
authors.affiliation: Central Veterinary Institute (CVI), Wageningen UR, PO Box 65, 8200 AB, Lelystad, The Netherlands. kees.veldman@wur.nl
authors.forename: Kees
authors.initials: K
authors.lastname: Veldman
authors.forename: Lina M
authors.initials: LM
authors.lastname: Cavaco
authors.forename: Dik
authors.initials: D
authors.lastname: Mevius
authors.forename: Antonio
authors.initials: A
authors.lastname: Battisti
authors.forename: Alessia
authors.initials: A
authors.lastname: Franco
authors.forename: Nadine
authors.initials: N
authors.lastname: Botteldoorn
authors.forename: Mireille
authors.initials: M
authors.lastname: Bruneau
authors.forename: Agnès
authors.initials: A
authors.lastname: Perrin-Guyomard
authors.forename: Tomas
authors.initials: T
authors.lastname: Cerny
authors.forename: Cristina
authors.initials: C
authors.lastname: De Frutos Escobar
authors.forename: Beatriz
authors.initials: B
authors.lastname: Guerra
authors.forename: Andreas
authors.initials: A
authors.lastname: Schroeter
authors.forename: Montserrat
authors.initials: M
authors.lastname: Gutierrez
authors.forename: Katie
authors.initials: K
authors.lastname: Hopkins
authors.forename: Anna-Liisa
authors.initials: AL
authors.lastname: Myllyniemi
authors.forename: Marianne
authors.initials: M
authors.lastname: Sunde
authors.forename: Dariusz
authors.initials: D
authors.lastname: Wasyl
authors.forename: Frank M
authors.initials: FM
authors.lastname: Aarestrup
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D024881:Drug Resistance, Bacterial; D004783:Environmental Microbiology; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary; D005060:Europe; D005516:Food Microbiology; D005798:Genes, Bacterial; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D010957:Plasmids; D016133:Polymerase Chain Reaction; D015363:Quinolones / Q000494:pharmacology*; D012189:Retrospective Studies; D012480:Salmonella Infections / Q000382:microbiology; D012481:Salmonella Infections, Animal / Q000382:microbiology; D019779:Salmonella enterica / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D017422:Sequence Analysis, DNA
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D015363:Quinolones